This is a renewal application for the California NeuroAIDS Tissue Network (CNTN) in response to the RFA- MH-13-070. The overarching objective ofthe CNTN remains the same today as it was when it was first established in 1998: to serve as a tissue bank resource comprised of CNS autopsy material from HIV- infected individuals who are well characterized neuropsychologically and neuromedically in life. The CNTN has been very successful in meeting this primary objective. To date, we have enrolled a total of 821 participants, including 303 autopsies, 39,600 aliquots of plasma, 27,500 aliquots of CSF, 18,700 aliquots of serum, and 5,600 aliquots of PBMCs. For the current application, we are restructuring our cohort to best target and obtain autopsies from high priority cases that are aligned'with the three thematic priorities identified in the RFA: a) HIV eradication from CNS reservoirs; b) mechanisms of HIV-associated neurocognitive disorders (HAND) in the setting of long term HAART, and c) HIV and aging. Specifically, we will target continuation of HIV+ participants who 1) are at greatest risk for death, 2) have been on ART for more than 10 years, and are greater than 50 years of age, which will provide valuable cases to the NNTC resource that are aligned with the NIH three thematic priorities. Specifically, we will recruit a cohort of 24 older (65+ years.old) participants from a new collaboration with the Eisenhower Medical Center (EMC) in Palm Springs given that more than 10% H1V+ persons in Riverside County are 65,or older. CNTN is an active participant in the National NeuroAIDS Tissue Consortium (NNTC), a partnership of four NIH-funded neuroAIDS tissue banks. CNTN contributes to the NNTC by: 1) leading the NNTC Neuropsychology and Psychiatry subcommittee and overseeing quality assurance for these data, 2) guiding the methods for historical antiretroviral collection, 3) contributing to the refinement ofthe common NNTC assessment and neuropathology protocols, 4) providing review and fulfillment of NNTC-wide tissue and sample requests, and 5) serving on the NNTC Steering Committee.. The CNTN will work closely with the NNTC to ensure continued success ofthis exceptional national and international resource for research on neuroAIDS. RELEVANCE (See instructions): HAND remains prevalent even now in the era of effective antiviral treatments for HIV. The CNTN, as part of the NNTC, provides neuromedical, neurocognitive, and psychiatric characterization in life and gathers brain and other tissues upon death. These data, fluids and tissues are made available to qualified investigators world-wide and are essential to uncovering the mechanisms associated with persistence of HAND.